Data commit

Task/Feigenbaum-constant-calculation/Nim/feigenbaum-constant-calculation.nim

@@ -0,0 +1,30 @@
+import strformat
+
+iterator feigenbaum(): tuple[n: int; δ: float] =
+  ## Yield successive approximations of Feigenbaum constant.
+
+  const
+    MaxI = 13
+    MaxJ = 10
+  var
+    a1 = 1.0
+    a2 = 0.0
+    δ = 3.2
+
+  for i in 2..MaxI:
+    var a = a1 + (a1 - a2) / δ
+    for j in 1..MaxJ:
+      var x, y = 0.0
+      for _ in 1..(1 shl i):
+        y = 1 - 2 * y * x
+        x = a - x * x
+      a -= x / y
+
+    δ = (a1 - a2) / (a - a1)
+    a2 = a1
+    a1 = a
+    yield (i, δ)
+
+echo " i         δ"
+for n, δ in feigenbaum():
+  echo fmt"{n:2d}    {δ:.8f}"